This invention relates generally to locomotion mechanism for dredging apparatus and associated method and, more particularly, to a spade wheel mechanism for propelling and maneuvering dredging apparatus in a body of water.
Various types of dredging apparatus are known in the art for removing silt, sand, mud or other sediment material from the bottom of a body of water. One such dredging apparatus is disclosed in U.S. Pat. No. 5,960,570 and includes a floatation arrangement operative to float on the surface of the body of water, a frame structure mounted on the floatation arrangement, and a silt excavating wheel mechanism rotatably mounted to the frame structure and operative to extract silt from under the body of water. Such apparatus also typically includes a height adjustment mechanism operative to raise and lower the excavating wheel mechanism relative to the surface of the water and may include a conveyor arrangement operative to transport the extracted silt away from the excavating wheel mechanism.
Typically, dredging apparatus likewise have mechanisms and/or systems for propelling and maneuvering the apparatus relative to the floor of the body of water. Usually, such drive mechanisms include a pair of drive wheels positioned one on each side of the dredging equipment to engage the floor of the body of water in order to propel and maneuver the dredging equipment relative thereto. However, due to the relatively loose, soft and slippery material typically present on the floor surfaces of bodies of water, the drive wheels may not always properly engage the floor surface whereby propelling or maneuvering such heavy equipment relative thereto becomes difficult, cumbersome and inefficient. Further, the contact between the drive wheels and the floor surface results in displacement of the relatively loose sediment material present at the floor surface into the surrounding water. Sediment material thus displaced causes undesirable turbidity in the surrounding water, which is particularly undesirable in the vicinity of the dredging wheel mechanism. It is accordingly preferable to minimize the amount of turbidity caused by the drive wheel mechanism associated with dredging apparatus during a dredging operation.
Therefore, it is desirable to provide a drive wheel mechanism for dredging apparatus which reliably engages the floor of a body of water during dredging operations, which permits efficient propulsion and navigation of the dredging apparatus relative to the floor of the body of water, and which does not cause turbidity in the vicinity of the dredging wheel mechanism during a dredging operation.
Accordingly, the present invention is directed to overcoming one or more of the problems as set forth above.
In one aspect of the present invention a drive wheel assembly adapted for use for propelling a dredging apparatus in a body of water is disclosed. The drive wheel assembly includes a carrier wheel rotatably coupled to the dredging apparatus, the carrier wheel including an axis member at the center thereof defining the center of rotation of the carrier wheel, a first member coupled to one end of the axis member and a second member coupled to the other end of the axis member, a pivotation member having opposed end portions, one end portion of the pivotation member being coupled to the center axis member of the carrier wheel, an orientation wheel pivotally connected to the opposed end portion of the pivotation member, and a plurality of spade devices pivotally connected to the carrier wheel and to the orientation wheel, each spade device including an arm portion and a blade portion, each arm portion having opposed end portions, one end portion of each arm portion being pivotally coupled to the orientation wheel and the opposite end portion of each arm portion being pivotally coupled to the first member associated with the carrier wheel, each blade portion having a portion thereof pivotally coupled to the second member associated with the carrier wheel whereby the spade devices are positioned in a substantially vertical orientation relation to the horizontal.
In another aspect of this invention, a method for assembling a drive wheel assembly adapted for use for propelling a dredging apparatus in a body of water is disclosed. The method includes the steps of rotatably coupling a carrier wheel to the dredging apparatus, the carrier wheel including an axis member at the center thereof defining the center of rotation of the carrier wheel, coupling a first member to one end of the axis member, coupling a second member to the other end of the axis member, pivotally connecting an orientation wheel to the opposed end portion of a pivotation member, the pivotation member having opposed end portions, one end portion of the pivotation member being coupled to the center axis member of the carrier wheel, pivotally connecting a plurality of spade devices to the carrier wheel and to the orientation wheel, each spade device including an arm portion and a blade portion, each arm portion having opposed end portions, pivotally coupling one end portion of each arm portion to the orientation wheel, pivotally coupling the opposite end portion of each arm portion to the first member associated with the carrier wheel, pivotally coupling each blade portion having a portion thereof to the second member associated with the carrier wheel, and positioning the spade devices in a substantially vertical orientation relation to the horizontal.
For a better understanding of the present invention, reference may be made to the accompanying drawings in which:
FIG. 1 is a partial top elevational view of a typical dredging apparatus incorporating the present invention;
FIG. 2 is a side view of a drive wheel assembly constructed according to one embodiment of the present invention; and
FIG. 3 is a front elevational view of the drive wheel assembly illustrated in FIG. 2.